Unseasonal rains in Western Australia and frost on the country's east coast have hit wheat crops in the world's No. 2 exporter of wheat, dragging down quality and reducing yields, reports Reuters.

The crop in parts of New South Wales and Victoria was hit by frost last month, although other regions of the eastern grain belt, including Queensland, have produced high-protein wheat.

GrainCorp last week warned of the impact of unfavourable weather in areas of New South Wales. "We expect the harvest (quality) to be revised down because of the frost damage," said Alison Watkins, the company's chief executive and managing director. "To what extent, is not yet clear."

Elsewhere, unseasonal rains are likely to hurt wheat quality and output in Western Australia, where harvesting is 10 per cent complete.

The November Crop & Pasture report for South Australia states that yields are likely to vary from average to well above average but are now significantly lower than earlier estimates due to a range of extreme weather events during spring.

• Strong to gale force winds in early to mid-October caused significant flattening of plants and head loss in ripe barley crops in several areas of the State with losses of 30 to 50% reported in some paddocks.
• Grain loss from wind damage was also reported in ripe wheat crops on Upper Eyre Peninsula.
• Wind also knocked canola crops down and caused significant grain shattering in crops planned to be direct cut.